The latest weapon in my armoury, a small glue gun. For my cardboard architectural models PVA adhesive proved a bit awkward to use, using a scrap of card as a spatula.
When I’m using the glue gun I find it difficult avoid the hot glue if I’m holding on to a tiny strip of card so I’m applying the glue to the main model then adding the strip of card to the tacky glue. It works well for me.